Once that you have an OID issued by HL7 UK, all the OID s “under” it, are yours to allocate as you see fit. You just need to keep a record internally.

For example:

  • If you have been allocated 2.16.840.1.113883.2.1.3.500
  • You can make:
    • 2.16.840.1.113883.2.1.3.500.1,
    • 2.16.840.1.113883.2.1.3.500.2
    • 2.16.840.1.113883.2.1.3.500.3 etc.
  • As well as:
    • 2.16.840.1.113883.2.1.3.500.1.1
    • 2.16.840.1.113883.2.1.3.500.1.1.1 etc.

In other words you could create:

  • [your oid].1
  • [your oid].2
  • [your oid].3 etc

And also levels:

  • [your oid].1.1
  • [your oid].1.1.1 etc

…and so on: as many levels and numbers as you like.

It’s probably best not to use the highest level numbers immediately but better to categorize them first:

  • [your oid].1 some category
  • [your oid].2 some other category
  • [your oid].3 etc

Fort example, you might want to create a top level one for “systems”

  • [your oid].1 Systems

Then have:

  • [your oid].1.1 LIMS
  • [your oid].1.2 PAS
  • [your oid].1.2 something else

…and so on

Then later you may want to allocate OIDs for eg Departments:

  • [your oid].2 Departments
  • [your oid].2.1 General Surgery
  • [your oid].2.2 A&E etc

This makes sure the two types (systems and departments) won’t be mixed up together.

Just make sure you keep a master catalogue – eg a spreadsheet or similar – somewhere central, ideally an intranet.